Ready-To-Eat cereal products (R-T-E) cereals are increasingly popular food products. Generally, such R-T-E cereal products are fabricated from a cooked cereal dough that is formed into suitably shaped and sized pieces or pellets which are then further processed to prepare the finished R-T-E cereal product.
Cooker extruders are increasingly used to process the raw materials of flour, sugar, adjuvants and water to prepare the cooked cereal dough. Cooker extruders have the advantage of requiring only very short processing times. Additionally, cooker extruders can process large quantities of products in a relatively short period of time.
In some applications, a cooked cereal product is extruded at low extrudate linear speeds such as when the extruder is equipped with a die face reciprocating knife cutter that segments the rope(s) extrudate into individual pieces. In other applications, the extrudate rope is fed into a collecting bin wherein the cooked cereal extrudate ropes form a cereal mass that is allowed to temper. In still other applications, the rope is extruded at low velocities and fed to a receiving conveyor belt which conveys the rope to the next processing station.
Under certain conditions, especially with high capacity cooker extruders, the extrudate rope exits the cooker extruder at high linear velocities. It is not uncommon for the ropes to exit at linear speeds of up to 160 meters per minute. One difficulty with such high speeds of extrudate is to convey the rope to the next processing station in a continuous rope form. Conventional conveyor belts have great difficulty in achieving such line speeds. Furthermore, feeding the ropes into downstream equipment is very difficult from a conventional conveyor belt at these speeds. Additionally, conveyor belts traveling at such high line speeds pose a significant potential for injury.
Still another problem concerns the importance of maintaining the shape of the cooked cereal dough extrudate. In certain R-T-E cereal applications, the extrudate rope exits the extruder in a soft, plastic state which often desirably experiences expansion or puffing immediately upon exiting the extruder die face. Conventional conveying means such as belt conveyors can result in deformation of the lower soft puffed portion of the extrudate rope that is in immediate contact with the belt conveyor.
Still another problem resides in the initial start-up of the extrudate rope. Initially, the linear exit velocity from the extruder may not be the same as when the cooker extruder is running at an established steady state operating condition. Accordingly, cooked cereal rope conveying apparatus must accommodate such variation in exit velocity without deforming (e.g., curling) the rope.
Still another problem is that frequently it is desirable to additionally condition the extrudate rope before the rope reaches the next processing station. Such condition might involve cooling, drying, and/or heating.
Surprisingly, the above problems can be overcome with improved apparatus and methods provided for conveying high velocity cooked cereal dough ropes without deformation and, optionally, with simultaneous conditioning. The improvement resides in providing an adjustable inlet and receiving member to a venturi eductor provided with motive air. In more preferred embodiments, the improvement further resides in providing a single manifold means for supplying high volumes of low pressure motive air to a plurality of such conveyance and conditioning tubes.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.